Objective To review the research of the artificial tracheal prosthesis in the past decade so as to provide theoretical references for the development of the artificial tracheal prosthesis. Methods The l iterature about the artificial tracheal prosthesis was extensively reviewed and analyzed. Results Many new materials are used for the research of artificialtracheal prosthesis which have excellent biocompatibil ity and stabil ity of the structural characteristics. And many compl ications such as migration, obstruction, and infection have been resolved, but so far none of the new materials has been used for cl inical treatment successfully. Conclusion The choice of the materials for artificial tracheal prosthesis is the key to succeed. Biodegradable polymer materials with its unique biological properties become the new direction of the tracheal prosthesis research.
Objective To isolate，culture and expand bone marrow mesenchymal stem cells （MSCs） in vitro，induce MSCs to differentiate directionally towards chondrocytes，and provide experimental basis for clinical application of MSCs and construction of tissue engineering tracheal cartilage. Methods Cultured MSCs were isolated from bone marrow of Sprague-Dawley rats，purified using adherence separation，and identified by flow cytometry analysis. Transforming growth factor β1 （TGF-β1）and insulin-like growth factor 1 （IGF-1） were used as main induction factors to induce MSCs to differentiate directionally towards chondrocytes. The expression of collagen typeⅡwas evaluated by immunocytochemical staining 21 days after induction. Light microscope and electron microscope were used to observe tiny and ultrastructural changes of the cells before and after induction. Results The expression of collagen typeⅡwas positive by immunocytochemical staining 21 days after induction. MSCs were fusiform before induction under light microscope and electron microscope. After induction，the cells became larger，polygon，star-shaped or triangular. Transmission electron microscope showed that the cells had abundant organelles，larger nuclei and more nucleoli after induction. Conclusion Abundant organelles，larger nuclei and more nucleoli are the ultrastructure changes of chondrocytes differentiated from MSCs，indicating that the cells are active in differentiation and metabolism.
Objective To review the recent research progress of the bioreactor biophysical factors in cartilage tissue engineering. Methods The related literature concerning the biophysical factors of bioreactor in cartilage tissue engineering was reviewed, analyzed, and summarized. Results Oxygen concentration, hydrostatic pressure, compressive force, and shear load in the bioreactor system have no unified standard parameters. Hydrostatic pressure and shear load have been in controversy, which restricts the application of bioreactors. Conclusion The biophysical factors of broreactor in cartilage tissue engineering have to be studied deeply.
Objective To summarize the recent progress of construction methods of engineered cell sheet and to forecast the possible prospect. Methods The recent original articles about investigation and appl ication of engineered cell sheet were reviewed. Several common methods were selected and expounded. Results The construction methods of engineered cell sheet mainly include temperature-responsive culture dish, salmon atelocollagen, magnetic force, surface roughness, and polyelectrolytes, which may overcome the l imits of traditional tissue engineering methods. Conclusion The construction methods of engineered cell sheet are feasible and have a bright future in the cl inical appl ication.
Decellularized tissue engineering scaffolds appear to have the properties of similar structure and mechanical characteristics to native tissues，good biocompatibility，suitability for cell adhesion，growth and angiogenesis induction，and non-immunogenicity. Genipin has anti-inflammatory，antithrombotic and antioxidative features which can considerably suppress vascular and endothelial inflammatory activation，increase mechanical strength of biological scaffolds，inhibit inflammatory response and decrease degradation rate of biological scaffolds. By cross-linking with decellularized matrices，Genipin can further improve corresponding performance of tissue engineering matrices，which is very helpful to promote the application of tissue engineering into clinical practice of cardiothoracic surgery. This review focuses on recent research process and possible prospects of Genipin cross-linking in tissue engineering in the field of cardiothoracic surgery.
Objective To summarize the recent research situation and progress of decellularized matrix in tissue engineered trachea transplantation and to forecast the possible perspects. Methods Recent original articles about study and application for decellularized matrix in tissue engineered trachea were reviewed. The application and study of different decellularized matrices involved in animals or patients with tracheal lesions were elaborated. Results Decellularized matrices researched and applied in tissue engineered trachea include jejunum, urinary bladder, aorta, and trachea. Conclusion Decellularized urinary bladder matrix and jejunal matrix appears to be efficacious method for the patch repair of partial circumferential tracheal defects. The application of decellularized aortic matrix may need more study, and decellularized tracheal matrix has a bright future in long tracheal defects.